Workpackage 3

Biogeochemistry and ecosystem functioning

Contributors

MPI, CIIMAR, AWI, GEOMAR, JUB, MARUM, NIOZ, UUtrecht, UGhent, UNIVPM

Goals and objectives

• Identification of the local spatial variability of sediment physical characteristics and biogeochemical processes in the study area

• Quantification of the changes induced by the collector trial with respect to the spatial extent of direct (e.g., surface sediment and nodule removal, sediment compaction, porewater release) and indirect mining impacts (sediment blanketing) on physical sediment properties (e.g., shear strength, water content), redox zonation, diagenetic fluxes (e.g., oxygen, nutrients, Mn, Fe, trace metals) and biogeochemical processes including particulate and dissolved organic matter degradation and trace metal reactions

• Effects of mining activities on microbial ecology and functions with a focus on organic matter remineralization, productivity, and mortality (microbiological and molecular tools, tracer incubations)

• Effects of suspended and resettled sediment plumes and differences in nodule coverage on organic matter remineralization by benthic communities, including microorganisms, meio-, macro- and megafauna (in situ experiments and food web models)